Do Now 4/20HW change: 34.9 ONLY

OBJECTIVE:

Identify and describe the characteristics of major terrestrial and aquatic biomes

TASK: Copy definition into notes:

A biome is a group of ecosystems in the biosphere with similar abiotic and biotic

components

So how many biomes are there?

• No fixed number

• 5, 7, 9, or more… depends on how specific you are

• We’ll look at 9….

What to do?

• Complete your chart as we discuss each biome.

Terrestrial Biomes

• Terrestrial biomes are land environments

• They are largely defined by patterns of precipitation and temperature.

Tundra• Tundra comes from

the Finnish word tunturia, meaning treeless plain.

• Extremely cold climate (covered by ice for > 6 months /yr)

• Low biotic diversity

• Permafrost• Short season of

growth and reproduction

• Energy and nutrients in the form of dead organic material

• Large population oscillations

Taiga• The average

temperature is below freezing for six months out of the year

• Drier than temperate forest

• There are not a lot of species of plants in the taiga because of the harsh conditions. Many coniferous trees. Needle-shaped leaves conserve water

• also known as the boreal forest. .

• Moderate temperature and rainfall• Diversity of plant and animal species, especially deciduous

trees (that lose their leaves in the autumn)• Pronounced seasons• Eastern US & Central Europe

Temperate Grassland

• Extremely fertile soil

• Dominated by grasses

• Semi-arid (10 – 30 inches of rain / year)

• “midwest”

Savanna• Hotter & wetter than

temperate grassland• warm temperature year round • Dry & Rainy “seasons”• Plants of the savannas are

highly specialized to grow in this environment of long periods of drought.

• Most of the animals on the savanna have long legs or wings to be able to go on long migrations

• Huge areas of savanna are lost to the Sahara desert every year because of overgrazing and farming.

• Very Dry! (<10 in. / yr)

• Usually hot, but defined by precipitation – Antarctica is a desert too!

• Specialized plants adapted to low moisture

Tropical Rain Forest

• abundant precipitation ( > 100 in. / year) and year round warmth.

• No seasons: each species has evolved its own flowering and fruiting seasons.

• Canopy of tree cover• Most biodiverse biome• Many unique, specialized species

Aquatic Biomes • Aquatic biomes are underwater, and there are

only two major types:– Freshwater– Marine

• Earth is a blue planet:– 70% of surface– Majority of organisms– Majority of photosynthesis– Abiogenesis / evolution

Freshwater Ecosystems

• Lakes, streams, rivers, marshes, and estuaries of all types.

• Great variety, due to abiotic factors like:– Salt concentration– Light availability– Dissolved O2, CO2, and other nutrients.

• Hypotonic environment.

Bull Falls, Shenandoah

Marine Ecosystems

Biome Review

• Tundra• Taiga• Temperate Deciduous Forest• Temperate Grassland• Desert• Savanna• Tropical Rain Forest• Others? (Chaparral)• Freshwater / Marine